Film, and process for producing the same

Abstract

Disclosed is a film which is knurling-processed without the facture of the film. Also disclosed is a method for producing the film. The film comprises a polymer resin film, in which a knurling processing is applied on both end parts in the width-wise direction on at least one surface of the film by irradiating the film with a laser beam.

1 . A polymeric resin film, wherein about at least one of its surfaces, both end regions thereof in the width direction of the film are subjected to knurling by radiation of a laser. 
     
     
         2 . The film according to  claim 1 , wherein when the average thickness of the region not subjected to the knurling is represented by T (μm) and the average thickness of both the end regions subjected to the knurling is represented by Tn (μm),
 T (μm) ranges from 20 to 70 μm and Tn−T ranges from 3 to 30 μm.   
     
     
         3 . The film according to  claim 1 , which has a tensile strength of 100 MPa or less and a tensile elongation of 80% or less. 
     
     
         4 . The film according to  claim 1 , wherein the regions subjected to the knurling are located in a band form in the longer direction in both the end regions of the film, and the width thereof ranges from 1 to 5% of the width of the film. 
     
     
         5 . The film according to  claim 1 , wherein concaves in the regions subjected to the knurling are formed at a density ranging from a density of 10 to 1000 per square centimeter. 
     
     
         6 . The film according to  claim 1 , wherein the planar shape of the concaves in the regions subjected to the knurling is circular. 
     
     
         7 . The film according to  claim 1 , wherein the polymeric resin film is an optical film. 
     
     
         8 . The film according to  claim 7 , wherein the optical film is a transparent protective film. 
     
     
         9 . The film according to  claim 8 , wherein the transparent protective film is a norbornene based film or an acrylic film. 
     
     
         10 . A polarizing plate wherein a film as recited in  claim 1  is set on at least one of surfaces of a polarizer. 
     
     
         11 . A process for producing a film, wherein about at least one of surfaces of a polymeric resin film, a laser is radiated onto both end regions thereof in the width direction of the film under predetermined conditions, thereby subjecting both the end regions to knurling. 
     
     
         12 . The process for producing a film according to  claim 11 , wherein the radiation of the laser is performed so as not to penetrate the film in such a manner that the power thereof is set into the range of 1 to 20 W.